Alpha, alpha-anthracene-dicarbonyl-chloride and process of preparing the same



Patented Feb. 19, 1935 a,a-ANTHRACENE DICARBONYL-CHLORIDE AND PROCESS OFPREPARING THE SAIVIE Ralph N. Lulek and Melvin A. Perkins, Milwaukee,

Wis., assignors to E. I. du Pont de Nemours & Company, Wilmington, Del.,a corporation of Delaware No Drawing.- Original application April 10,1933,

Serial No. 665,441. Divided and thisapplication August 26, 1933, SerialNo. 687,011 1 7 Claims. 01. 260-123) This application is a division ofour copending application Ser. No. 665,441, filed April 10, 1933.

The invention herein described deals with novel organic compounds whichmay be used as intermediates for vat dyestuffs.

More particularly, this invention deals witha,a-anthracene-dicarbonyl-chlorides of the general formula V wherein Xstands for another COCl group in an alpha position. 7 We prepare thesenovel compounds by starting with the corresponding (1,0;-anthracene-dicarboxylic acid and converting the same in the usual mannerinto the correspond- 7 Example 1 15 parts of 1,4-anthracene-dicarboxylicacid, obtained from the corresponding anthraquinonedicarboxylic acid byreduction with zinc and ammonia (Elbs, Journal fiir Praktische Chemie(2) 41, 30, and Phillips, Journal of the American Chemical Society, 46,2533), are introduced into 45 parts of water-free benzol at roomtemperature. 25 parts of phosphorus pentachloride are now added and themixture is agitated until nearly all is in solution. Heat is thenapplied gently and the solution is heated to reflux for about 15 minutesor until hydrochloric acid evolution has ceased. The darkireddishsolution is then allowed to cool. slowly, separating deep red crystals.Agitation is then applied and parts of petroleum ether are added. Thered crystals are filtered by suction, washed with petroleum ether parts)and dried. The yield is good and the deep red crystalline product acidch1oride='23.4%

V Example 2 10 parts of 1,5-anthracene-dicarboxylic acid (pale,greenish-yellow solid made by reduction of1,5-anthraquinone-dicarboxylic acid by means of zinc and ammonia-Scholl,Berichte, 62, 109) are 5 suspended in 50, parts of water-free benzol and16.5 parts of phosphorus pentachloride are added. The reaction isallowed to proceed without external application of heat for one hour,after which heat is applied gently. The solid gradually goes intosolution. Heating is continued until the solution has refluxed for aboutone-half hour or until hydrochloric acid evolution ceases.

Upon cooling, greenish-yellow crystals appear. The mass is dilutedwithan equal volume of petroleum ether, filtered, and the1,5-anthracenedicarboxylicacid chloride washed with petroleum ether anddried. It forms a dull green-yellow powder and contains a quantity ofchlorine corresponding to two atoms. 20

It will be understood that many variations and modifications arepossible in the specific procedures above set forth without departingfrom the spirit of this invention.

For instance, the formation of the anthracene acid chlorides may bemodified according to ans well known procedure for preparing acidchlorides from the corresponding carboxylic acids. Thus, instead ofbenzol, phosphorus oxy-chloride may be used as solvent. Or the solventmay be omitted altogether, the reactants'being merely fused together.Instead of phosphorus pentachloride, thionyl chloride may be used aschlorinating agent.

We claim: 7 35 1. A compound of the general formula:

wherein X stands for another 0001 group in the 4 or 5 position.

2. 1,5-anthracene dicarbonyl-chloride. 3.1,4-anthracene-dicarbonyl-chloride. 4. The process of producing an.u,a-dicarbony l chloride of anthracene, which comprises reacting anu,a-anthracene-dicarboxylic acidwith an acid chlorinating agent. Y

5. The process of producing an u,a-a'nthracenedicarbonyl-chloride, whichcomprises reacting an v5 u,u-anthracene-dicarboxylic acid withphosphorus pentachloride.

6. The process of producing LS-anthracenedicarbonyl-chloridg; whichcomprises reacting phos-i which comprises reacting

